Geometry collection - source geometry not updating and reset bug

UE - Simulation - Core - Aug 17, 2023

This issue was reported by a customer trying to modify the static meshes of a GeometryCollection. After removing some meshes from the Geometry Source, he used the Reset button to apply the changes t ...

Navmesh doesn't work in a Packaged Build if it was placed in a Sublevel

UE - AI - Oct 19, 2018

Once packaged, a persistent level is unable to create navmesh data properly if the navmesh bounds volumes are only present in its sublevels. The issue can be traced to the UNavigationSystemV1::IsThe ...

Editor Crashes When a Component and Actor Implement Two Interfaces

UE - Gameplay - Blueprint - Oct 16, 2015

The editor crashes if you implement two blueprint interfaces in an actor blueprint, and then an actor component blueprint. These interfaces must have at least one function that returns a value. The ...

Post increment operator is not overridden for data structure iteration

UE - Foundation - Core - Mar 21, 2017

Attempting to use a post increment operator in a TMap or TSet iterator will fail to compile with error shown in callstack field. This is due to the post-increment operator not being overridden in M ...

Unable to pause Camera Shake if Google VR plugin is enabled

UE - Platform - XR - Jun 22, 2017

Unable to pause Camera Shake if Google VR plugin is enabled. Everything pauses correctly if the Google VR plugin is disabled. Unable to test in Main due to blocker with enabling Google VR plugin. ...

Initial Modules are clamped to a 0 to 1 time range

UE - Graphics Features - Sep 18, 2015

The Initial Modules appear to be clamped to a zero to 1 time frame since 4.8 was released. Projects that are converted from 4.7.6 will have correctly working particle systems, but adding a new part ...

GAMEPLAYATTRIBUTE_REPNOTIFY does not properly propagate OldValue

UE - Gameplay - Dec 10, 2021

Associated UDN [Link Removed] We've been having some issues with the replication of attributes. Namely we have an OnRep_ function for an attribute that receives FGameplayAttributeData& OldValue a ...

Blueprints derived from "Editor Utility Actor" are not able to tick in editor when placed in the world

Tools - Sep 11, 2019

Placed Editor Utility Base was recently deprecated and users who require the functionality of ticking in the editor are unable to use "Editor Utility Actor" or "Editor Utility Widget." A couple of u ...

SpeedTree Material No Longer Compiles With Texture Coordinate Node In BaseColor

UE - Graphics Features - Jan 25, 2017

If you open a material with the speedtree node plugged into WPO and then use a texture coordinate(index of 2) in base color the material will no longer compile properly. The full error is "Error [ ...

Wrong calculation of "MaxAllocatedCountEstimate" inside FNiagaraRendererRibbons::GenerateDynamicData()

UE - Niagara - Mar 20, 2026

Starting with UE 5.4, function FNiagaraRendererRibbons::GenerateDynamicData() from file [NiagaraRendererRibbons.cpp] attempts to calculate DynamicData->MaxAllocatedCountEstimate as such: DynamicDat ...